[mirror_ubuntu-zesty-kernel.git] / fs / hfsplus / inode.c

/*
 *  linux/fs/hfsplus/inode.c
 *
 * Copyright (C) 2001
 * Brad Boyer (flar@allandria.com)
 * (C) 2003 Ardis Technologies <roman@ardistech.com>
 *
 * Inode handling routines
 */

#include <linux/blkdev.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/mpage.h>
#include <linux/sched.h>

#include "hfsplus_fs.h"
#include "hfsplus_raw.h"

static int hfsplus_readpage(struct file *file, struct page *page)
{
        return block_read_full_page(page, hfsplus_get_block);
}

static int hfsplus_writepage(struct page *page, struct writeback_control *wbc)
{
        return block_write_full_page(page, hfsplus_get_block, wbc);
}

static int hfsplus_write_begin(struct file *file, struct address_space *mapping,
                        loff_t pos, unsigned len, unsigned flags,
                        struct page **pagep, void **fsdata)
{
        int ret;

        *pagep = NULL;
        ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
                                hfsplus_get_block,
                                &HFSPLUS_I(mapping->host)->phys_size);
        if (unlikely(ret)) {
                loff_t isize = mapping->host->i_size;
                if (pos + len > isize)
                        vmtruncate(mapping->host, isize);
        }

        return ret;
}

static sector_t hfsplus_bmap(struct address_space *mapping, sector_t block)
{
        return generic_block_bmap(mapping, block, hfsplus_get_block);
}

static int hfsplus_releasepage(struct page *page, gfp_t mask)
{
        struct inode *inode = page->mapping->host;
        struct super_block *sb = inode->i_sb;
        struct hfs_btree *tree;
        struct hfs_bnode *node;
        u32 nidx;
        int i, res = 1;

        switch (inode->i_ino) {
        case HFSPLUS_EXT_CNID:
                tree = HFSPLUS_SB(sb)->ext_tree;
                break;
        case HFSPLUS_CAT_CNID:
                tree = HFSPLUS_SB(sb)->cat_tree;
                break;
        case HFSPLUS_ATTR_CNID:
                tree = HFSPLUS_SB(sb)->attr_tree;
                break;
        default:
                BUG();
                return 0;
        }
        if (!tree)
                return 0;
        if (tree->node_size >= PAGE_CACHE_SIZE) {
                nidx = page->index >>
                        (tree->node_size_shift - PAGE_CACHE_SHIFT);
                spin_lock(&tree->hash_lock);
                node = hfs_bnode_findhash(tree, nidx);
                if (!node)
                        ;
                else if (atomic_read(&node->refcnt))
                        res = 0;
                if (res && node) {
                        hfs_bnode_unhash(node);
                        hfs_bnode_free(node);
                }
                spin_unlock(&tree->hash_lock);
        } else {
                nidx = page->index <<
                        (PAGE_CACHE_SHIFT - tree->node_size_shift);
                i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
                spin_lock(&tree->hash_lock);
                do {
                        node = hfs_bnode_findhash(tree, nidx++);
                        if (!node)
                                continue;
                        if (atomic_read(&node->refcnt)) {
                                res = 0;
                                break;
                        }
                        hfs_bnode_unhash(node);
                        hfs_bnode_free(node);
                } while (--i && nidx < tree->node_count);
                spin_unlock(&tree->hash_lock);
        }
        return res ? try_to_free_buffers(page) : 0;
}

static ssize_t hfsplus_direct_IO(int rw, struct kiocb *iocb,
                const struct iovec *iov, loff_t offset, unsigned long nr_segs)
{
        struct file *file = iocb->ki_filp;
        struct inode *inode = file->f_path.dentry->d_inode->i_mapping->host;
        ssize_t ret;

        ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
                                 hfsplus_get_block);

        /*
         * In case of error extending write may have instantiated a few
         * blocks outside i_size. Trim these off again.
         */
        if (unlikely((rw & WRITE) && ret < 0)) {
                loff_t isize = i_size_read(inode);
                loff_t end = offset + iov_length(iov, nr_segs);

                if (end > isize)
                        vmtruncate(inode, isize);
        }

        return ret;
}

static int hfsplus_writepages(struct address_space *mapping,
                              struct writeback_control *wbc)
{
        return mpage_writepages(mapping, wbc, hfsplus_get_block);
}

const struct address_space_operations hfsplus_btree_aops = {
        .readpage       = hfsplus_readpage,
        .writepage      = hfsplus_writepage,
        .write_begin    = hfsplus_write_begin,
        .write_end      = generic_write_end,
        .bmap           = hfsplus_bmap,
        .releasepage    = hfsplus_releasepage,
};

const struct address_space_operations hfsplus_aops = {
        .readpage       = hfsplus_readpage,
        .writepage      = hfsplus_writepage,
        .write_begin    = hfsplus_write_begin,
        .write_end      = generic_write_end,
        .bmap           = hfsplus_bmap,
        .direct_IO      = hfsplus_direct_IO,
        .writepages     = hfsplus_writepages,
};

const struct dentry_operations hfsplus_dentry_operations = {
        .d_hash       = hfsplus_hash_dentry,
        .d_compare    = hfsplus_compare_dentry,
};

static struct dentry *hfsplus_file_lookup(struct inode *dir,
                struct dentry *dentry, struct nameidata *nd)
{
        struct hfs_find_data fd;
        struct super_block *sb = dir->i_sb;
        struct inode *inode = NULL;
        struct hfsplus_inode_info *hip;
        int err;

        if (HFSPLUS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
                goto out;

        inode = HFSPLUS_I(dir)->rsrc_inode;
        if (inode)
                goto out;

        inode = new_inode(sb);
        if (!inode)
                return ERR_PTR(-ENOMEM);

        hip = HFSPLUS_I(inode);
        inode->i_ino = dir->i_ino;
        INIT_LIST_HEAD(&hip->open_dir_list);
        mutex_init(&hip->extents_lock);
        hip->extent_state = 0;
        hip->flags = 0;
        set_bit(HFSPLUS_I_RSRC, &hip->flags);

        hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
        err = hfsplus_find_cat(sb, dir->i_ino, &fd);
        if (!err)
                err = hfsplus_cat_read_inode(inode, &fd);
        hfs_find_exit(&fd);
        if (err) {
                iput(inode);
                return ERR_PTR(err);
        }
        hip->rsrc_inode = dir;
        HFSPLUS_I(dir)->rsrc_inode = inode;
        igrab(dir);

        /*
         * __mark_inode_dirty expects inodes to be hashed.  Since we don't
         * want resource fork inodes in the regular inode space, we make them
         * appear hashed, but do not put on any lists.  hlist_del()
         * will work fine and require no locking.
         */
        hlist_add_fake(&inode->i_hash);

        mark_inode_dirty(inode);
out:
        d_add(dentry, inode);
        return NULL;
}

static void hfsplus_get_perms(struct inode *inode,
                struct hfsplus_perm *perms, int dir)
{
        struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
        u16 mode;

        mode = be16_to_cpu(perms->mode);

        inode->i_uid = be32_to_cpu(perms->owner);
        if (!inode->i_uid && !mode)
                inode->i_uid = sbi->uid;

        inode->i_gid = be32_to_cpu(perms->group);
        if (!inode->i_gid && !mode)
                inode->i_gid = sbi->gid;

        if (dir) {
                mode = mode ? (mode & S_IALLUGO) : (S_IRWXUGO & ~(sbi->umask));
                mode |= S_IFDIR;
        } else if (!mode)
                mode = S_IFREG | ((S_IRUGO|S_IWUGO) & ~(sbi->umask));
        inode->i_mode = mode;

        HFSPLUS_I(inode)->userflags = perms->userflags;
        if (perms->rootflags & HFSPLUS_FLG_IMMUTABLE)
                inode->i_flags |= S_IMMUTABLE;
        else
                inode->i_flags &= ~S_IMMUTABLE;
        if (perms->rootflags & HFSPLUS_FLG_APPEND)
                inode->i_flags |= S_APPEND;
        else
                inode->i_flags &= ~S_APPEND;
}

static int hfsplus_file_open(struct inode *inode, struct file *file)
{
        if (HFSPLUS_IS_RSRC(inode))
                inode = HFSPLUS_I(inode)->rsrc_inode;
        if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
                return -EOVERFLOW;
        atomic_inc(&HFSPLUS_I(inode)->opencnt);
        return 0;
}

static int hfsplus_file_release(struct inode *inode, struct file *file)
{
        struct super_block *sb = inode->i_sb;

        if (HFSPLUS_IS_RSRC(inode))
                inode = HFSPLUS_I(inode)->rsrc_inode;
        if (atomic_dec_and_test(&HFSPLUS_I(inode)->opencnt)) {
                mutex_lock(&inode->i_mutex);
                hfsplus_file_truncate(inode);
                if (inode->i_flags & S_DEAD) {
                        hfsplus_delete_cat(inode->i_ino,
                                           HFSPLUS_SB(sb)->hidden_dir, NULL);
                        hfsplus_delete_inode(inode);
                }
                mutex_unlock(&inode->i_mutex);
        }
        return 0;
}

static int hfsplus_setattr(struct dentry *dentry, struct iattr *attr)
{
        struct inode *inode = dentry->d_inode;
        int error;

        error = inode_change_ok(inode, attr);
        if (error)
                return error;

        if ((attr->ia_valid & ATTR_SIZE) &&
            attr->ia_size != i_size_read(inode)) {
                inode_dio_wait(inode);

                error = vmtruncate(inode, attr->ia_size);
                if (error)
                        return error;
        }

        setattr_copy(inode, attr);
        mark_inode_dirty(inode);
        return 0;
}

int hfsplus_file_fsync(struct file *file, int datasync)
{
        struct inode *inode = file->f_mapping->host;
        struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
        struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
        int error = 0, error2;

        /*
         * Sync inode metadata into the catalog and extent trees.
         */
        sync_inode_metadata(inode, 1);

        /*
         * And explicitly write out the btrees.
         */
        if (test_and_clear_bit(HFSPLUS_I_CAT_DIRTY, &hip->flags))
                error = filemap_write_and_wait(sbi->cat_tree->inode->i_mapping);

        if (test_and_clear_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags)) {
                error2 =
                        filemap_write_and_wait(sbi->ext_tree->inode->i_mapping);
                if (!error)
                        error = error2;
        }

        if (test_and_clear_bit(HFSPLUS_I_ALLOC_DIRTY, &hip->flags)) {
                error2 = filemap_write_and_wait(sbi->alloc_file->i_mapping);
                if (!error)
                        error = error2;
        }

        if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
                blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);

        return error;
}

static const struct inode_operations hfsplus_file_inode_operations = {
        .lookup         = hfsplus_file_lookup,
        .truncate       = hfsplus_file_truncate,
        .setattr        = hfsplus_setattr,
        .setxattr       = hfsplus_setxattr,
        .getxattr       = hfsplus_getxattr,
        .listxattr      = hfsplus_listxattr,
};

static const struct file_operations hfsplus_file_operations = {
        .llseek         = generic_file_llseek,
        .read           = do_sync_read,
        .aio_read       = generic_file_aio_read,
        .write          = do_sync_write,
        .aio_write      = generic_file_aio_write,
        .mmap           = generic_file_mmap,
        .splice_read    = generic_file_splice_read,
        .fsync          = hfsplus_file_fsync,
        .open           = hfsplus_file_open,
        .release        = hfsplus_file_release,
        .unlocked_ioctl = hfsplus_ioctl,
};

struct inode *hfsplus_new_inode(struct super_block *sb, int mode)
{
        struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
        struct inode *inode = new_inode(sb);
        struct hfsplus_inode_info *hip;

        if (!inode)
                return NULL;

        inode->i_ino = sbi->next_cnid++;
        inode->i_mode = mode;
        inode->i_uid = current_fsuid();
        inode->i_gid = current_fsgid();
        inode->i_nlink = 1;
        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;

        hip = HFSPLUS_I(inode);
        INIT_LIST_HEAD(&hip->open_dir_list);
        mutex_init(&hip->extents_lock);
        atomic_set(&hip->opencnt, 0);
        hip->extent_state = 0;
        hip->flags = 0;
        memset(hip->first_extents, 0, sizeof(hfsplus_extent_rec));
        memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
        hip->alloc_blocks = 0;
        hip->first_blocks = 0;
        hip->cached_start = 0;
        hip->cached_blocks = 0;
        hip->phys_size = 0;
        hip->fs_blocks = 0;
        hip->rsrc_inode = NULL;
        if (S_ISDIR(inode->i_mode)) {
                inode->i_size = 2;
                sbi->folder_count++;
                inode->i_op = &hfsplus_dir_inode_operations;
                inode->i_fop = &hfsplus_dir_operations;
        } else if (S_ISREG(inode->i_mode)) {
                sbi->file_count++;
                inode->i_op = &hfsplus_file_inode_operations;
                inode->i_fop = &hfsplus_file_operations;
                inode->i_mapping->a_ops = &hfsplus_aops;
                hip->clump_blocks = sbi->data_clump_blocks;
        } else if (S_ISLNK(inode->i_mode)) {
                sbi->file_count++;
                inode->i_op = &page_symlink_inode_operations;
                inode->i_mapping->a_ops = &hfsplus_aops;
                hip->clump_blocks = 1;
        } else
                sbi->file_count++;
        insert_inode_hash(inode);
        mark_inode_dirty(inode);
        sb->s_dirt = 1;

        return inode;
}

void hfsplus_delete_inode(struct inode *inode)
{
        struct super_block *sb = inode->i_sb;

        if (S_ISDIR(inode->i_mode)) {
                HFSPLUS_SB(sb)->folder_count--;
                sb->s_dirt = 1;
                return;
        }
        HFSPLUS_SB(sb)->file_count--;
        if (S_ISREG(inode->i_mode)) {
                if (!inode->i_nlink) {
                        inode->i_size = 0;
                        hfsplus_file_truncate(inode);
                }
        } else if (S_ISLNK(inode->i_mode)) {
                inode->i_size = 0;
                hfsplus_file_truncate(inode);
        }
        sb->s_dirt = 1;
}

void hfsplus_inode_read_fork(struct inode *inode, struct hfsplus_fork_raw *fork)
{
        struct super_block *sb = inode->i_sb;
        struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
        struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
        u32 count;
        int i;

        memcpy(&hip->first_extents, &fork->extents, sizeof(hfsplus_extent_rec));
        for (count = 0, i = 0; i < 8; i++)
                count += be32_to_cpu(fork->extents[i].block_count);
        hip->first_blocks = count;
        memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
        hip->cached_start = 0;
        hip->cached_blocks = 0;

        hip->alloc_blocks = be32_to_cpu(fork->total_blocks);
        hip->phys_size = inode->i_size = be64_to_cpu(fork->total_size);
        hip->fs_blocks =
                (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
        inode_set_bytes(inode, hip->fs_blocks << sb->s_blocksize_bits);
        hip->clump_blocks =
                be32_to_cpu(fork->clump_size) >> sbi->alloc_blksz_shift;
        if (!hip->clump_blocks) {
                hip->clump_blocks = HFSPLUS_IS_RSRC(inode) ?
                        sbi->rsrc_clump_blocks :
                        sbi->data_clump_blocks;
        }
}

void hfsplus_inode_write_fork(struct inode *inode,
                struct hfsplus_fork_raw *fork)
{
        memcpy(&fork->extents, &HFSPLUS_I(inode)->first_extents,
               sizeof(hfsplus_extent_rec));
        fork->total_size = cpu_to_be64(inode->i_size);
        fork->total_blocks = cpu_to_be32(HFSPLUS_I(inode)->alloc_blocks);
}

int hfsplus_cat_read_inode(struct inode *inode, struct hfs_find_data *fd)
{
        hfsplus_cat_entry entry;
        int res = 0;
        u16 type;

        type = hfs_bnode_read_u16(fd->bnode, fd->entryoffset);

        HFSPLUS_I(inode)->linkid = 0;
        if (type == HFSPLUS_FOLDER) {
                struct hfsplus_cat_folder *folder = &entry.folder;

                if (fd->entrylength < sizeof(struct hfsplus_cat_folder))
                        /* panic? */;
                hfs_bnode_read(fd->bnode, &entry, fd->entryoffset,
                                        sizeof(struct hfsplus_cat_folder));
                hfsplus_get_perms(inode, &folder->permissions, 1);
                inode->i_nlink = 1;
                inode->i_size = 2 + be32_to_cpu(folder->valence);
                inode->i_atime = hfsp_mt2ut(folder->access_date);
                inode->i_mtime = hfsp_mt2ut(folder->content_mod_date);
                inode->i_ctime = hfsp_mt2ut(folder->attribute_mod_date);
                HFSPLUS_I(inode)->create_date = folder->create_date;
                HFSPLUS_I(inode)->fs_blocks = 0;
                inode->i_op = &hfsplus_dir_inode_operations;
                inode->i_fop = &hfsplus_dir_operations;
        } else if (type == HFSPLUS_FILE) {
                struct hfsplus_cat_file *file = &entry.file;

                if (fd->entrylength < sizeof(struct hfsplus_cat_file))
                        /* panic? */;
                hfs_bnode_read(fd->bnode, &entry, fd->entryoffset,
                                        sizeof(struct hfsplus_cat_file));

                hfsplus_inode_read_fork(inode, HFSPLUS_IS_RSRC(inode) ?
                                        &file->rsrc_fork : &file->data_fork);
                hfsplus_get_perms(inode, &file->permissions, 0);
                inode->i_nlink = 1;
                if (S_ISREG(inode->i_mode)) {
                        if (file->permissions.dev)
                                inode->i_nlink =
                                        be32_to_cpu(file->permissions.dev);
                        inode->i_op = &hfsplus_file_inode_operations;
                        inode->i_fop = &hfsplus_file_operations;
                        inode->i_mapping->a_ops = &hfsplus_aops;
                } else if (S_ISLNK(inode->i_mode)) {
                        inode->i_op = &page_symlink_inode_operations;
                        inode->i_mapping->a_ops = &hfsplus_aops;
                } else {
                        init_special_inode(inode, inode->i_mode,
                                           be32_to_cpu(file->permissions.dev));
                }
                inode->i_atime = hfsp_mt2ut(file->access_date);
                inode->i_mtime = hfsp_mt2ut(file->content_mod_date);
                inode->i_ctime = hfsp_mt2ut(file->attribute_mod_date);
                HFSPLUS_I(inode)->create_date = file->create_date;
        } else {
                printk(KERN_ERR "hfs: bad catalog entry used to create inode\n");
                res = -EIO;
        }
        return res;
}

int hfsplus_cat_write_inode(struct inode *inode)
{
        struct inode *main_inode = inode;
        struct hfs_find_data fd;
        hfsplus_cat_entry entry;

        if (HFSPLUS_IS_RSRC(inode))
                main_inode = HFSPLUS_I(inode)->rsrc_inode;

        if (!main_inode->i_nlink)
                return 0;

        if (hfs_find_init(HFSPLUS_SB(main_inode->i_sb)->cat_tree, &fd))
                /* panic? */
                return -EIO;

        if (hfsplus_find_cat(main_inode->i_sb, main_inode->i_ino, &fd))
                /* panic? */
                goto out;

        if (S_ISDIR(main_inode->i_mode)) {
                struct hfsplus_cat_folder *folder = &entry.folder;

                if (fd.entrylength < sizeof(struct hfsplus_cat_folder))
                        /* panic? */;
                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
                                        sizeof(struct hfsplus_cat_folder));
                /* simple node checks? */
                hfsplus_cat_set_perms(inode, &folder->permissions);
                folder->access_date = hfsp_ut2mt(inode->i_atime);
                folder->content_mod_date = hfsp_ut2mt(inode->i_mtime);
                folder->attribute_mod_date = hfsp_ut2mt(inode->i_ctime);
                folder->valence = cpu_to_be32(inode->i_size - 2);
                hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
                                         sizeof(struct hfsplus_cat_folder));
        } else if (HFSPLUS_IS_RSRC(inode)) {
                struct hfsplus_cat_file *file = &entry.file;
                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
                               sizeof(struct hfsplus_cat_file));
                hfsplus_inode_write_fork(inode, &file->rsrc_fork);
                hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
                                sizeof(struct hfsplus_cat_file));
        } else {
                struct hfsplus_cat_file *file = &entry.file;

                if (fd.entrylength < sizeof(struct hfsplus_cat_file))
                        /* panic? */;
                hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
                                        sizeof(struct hfsplus_cat_file));
                hfsplus_inode_write_fork(inode, &file->data_fork);
                hfsplus_cat_set_perms(inode, &file->permissions);
                if (HFSPLUS_FLG_IMMUTABLE &
                                (file->permissions.rootflags |
                                        file->permissions.userflags))
                        file->flags |= cpu_to_be16(HFSPLUS_FILE_LOCKED);
                else
                        file->flags &= cpu_to_be16(~HFSPLUS_FILE_LOCKED);
                file->access_date = hfsp_ut2mt(inode->i_atime);
                file->content_mod_date = hfsp_ut2mt(inode->i_mtime);
                file->attribute_mod_date = hfsp_ut2mt(inode->i_ctime);
                hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
                                         sizeof(struct hfsplus_cat_file));
        }

        set_bit(HFSPLUS_I_CAT_DIRTY, &HFSPLUS_I(inode)->flags);
out:
        hfs_find_exit(&fd);
        return 0;
}